How to Tell If a Watermelon Is Ripe

Every year, I face the same dilemma: how to tell if a watermelon is ripe. Muskmelons are easy—they will slip right off the vine at the peak of perfection. However, watermelons remain firmly attached even when they are overripe.

I am no good at the “thump” test. Old-timers swear they know when a watermelon is ripe just by rapping it with a knuckle. It is ready if the sound is low-pitched, hollow, and deep like a drum. Johnny’s Seed Company explains further, saying that it should sound like a “punk” rather than a “pink” or a “pank” when you flick it with your finger. I have failed miserably at this test in years past, picking unripe melons that are still white inside. Once they are detached from the vine, watermelons won’t continue to ripen. You only get one chance to do this right!

When all else fails, I guess I should look at the seed packet. It says that my Sugar Babies should be ripe in 80 days from planting, and though we started the seeds indoors in early May, they did not get planted in the garden until early June. I think they should be ready any day now, but since they do most of their ripening in the last 2 weeks of growth, it is important not to jump the gun.

Tricks to Tell if a Watermelon is Ripe

Here are other subtle cues to look out for:

• The green color becomes dull.
• On striped melons, the color between the stripes gets darker.
• The rind will get hard.
• The blossom end will soften.
• They will stop getting larger.
• The ground spot will turn from white to yellow.
• The end of the main vine nearest the fruit may start to crack or turn brown.
• The curly tendril on the main vine, closest to the fruit, will turn brown.

Do you have any tried and true method of determining the ripeness of a watermelon that you’d like to share?

See more about harvesting watermelons in the Almanac’s Watermelon Growing Guide.

How do YOU tell that your watermelon is ripe? Do you have any sure-fire tips? We want to hear all about them!